> I think the problem is with the definition of IsNumber in Help. It

> takes an argument of "Value" and then refers to "Value" as the

> "specified text". A better definition might be:

>

> $IsNumber*("Str")$ *Returns 1 if Str contains only digits 0 through 9,

> and 0 if it does not.

>

> This explains what you observe. The fact that these numbers are

> integers is just a coincidence. This definition also corresponds more

> closely to the definition of IsAlpha.

>

> It also might have avoided this whole thread. :-)

Your definition would have indeed been better than the one provided ...

but I think it is more accurate to say integers (defined as all whole

numbers positive AND NEGATIVE and zero:

http://en.wikipedia.org/wiki/Integer ). Your definition forgot the

negative sign ... that is not a 0-9 character ... and can only appear

immediately preceeding the number:

^!Info [C] minus 5 -- ^$IsNumber("-5")$

^!Info [C] 5 minus -- ^$IsNumber("5-")$

^!Info [C] 5 minus 5 -- ^$IsNumber("5-5")$

This tread would have still been necessary because what I needed to do

was test if something was a number in this format ([brackets mean

optional] and ... ellipses means one or more):

[#...][,][##]#[.][#...]

As isnumber didn't cover my situation ... I had to come up with a way to

do it.

Is is possible to test if something is a "number" with a regex?

Rules:

1. either one or no decimal point, but there can be any number of proper

characters before and after the decimal

2. comma's are permitted but not required, but may only be present with

three proper characters to the right of each comma and left of the

decimal (or implied decimal if it is an integer)

3. proper characters are 0-9, an no other characters are permitted

except for rule 1 (decimal point) and rule 2 (properly placed commas)

I wrote a clip function to do it, but if there is a regex that would do

it quicker ...

I just did this:

a+b+c+d+e+t+x+y=0

But the fact that those letters for some reason have a numeric value of

zero when used in calculations DOES NOT make them numbers per isnumber

when not used in calculations, as each of the following tests negative:

^!Info [C]abcdetxy --^$IsNumber("abcdetxy")$

^!Info [C]a --^$IsNumber("a")$

^!Info [C]aa --^$IsNumber("aa")$

^!Info [C]e --^$IsNumber("e")$

But when we use calc, we are all over the place ...

^!Info [C]abcdetxy --^$IsNumber("^$Calc(abcdetxy)$")$

^!Info [C]a --^$IsNumber("^$Calc(a)$")$

^!Info [C]aa --^$IsNumber("^$Calc(aa)$")$

^!Info [C]a*a --^$IsNumber("^$Calc(a*a)$")$

^!Info [C]e --^$IsNumber("^$Calc(e)$")$

Anyway, I am enjoying the tread and hope deep in my heart that this bug

just might be the catalyst to get Eric coding either an update or better

yet, a version 5. As I said a few months back though, I am not sure a

version 5 is really going to happen and nobody has told me I am wrong by

giving me any milestones, targets or goals. I'd settle for 4.96 with

this bug fixed and isnumber better defined in help ;-)